Fault Finding - EHC Fusion Installation & Technical Manual

Symptom
The indicators on the front panel
are off
The „B" indicator is flickering
The room thermostat indicates
that the boiler is switched on.
„C" indicator does not light
The „D" or „E" indicator are
blinking
2
1
7
8
11
16
14
GB-016C_f.493

FAULT FINDING

Reason
No power to the boiler
Main over heat stat cut-out
Flow sensor is blocked
Circulating pump is blocked
Flow sensor failure
Control panel fuse failure
Temperature sensor failure
3
4
9
5
6
10
12
15
13
Check electricity mains power supply
Check the power board fuse F2
Check the WT3 temperature safety cut-out investige cause - possibly
fault / return sensors
Check flow sensor
The central heating system airlock - vent the central heating system
and the pump
Check for choked pipes
Move the pump rotor manually
Check the flow sensor and replace if neccesary.
Find the failure reason then replace the fuse.
Check external controls, room stats, etc. are calling for heat.
Link out control stats connections to eliminate external controls
If boiler operates the fault is with the external controls
Replace temperature sensor.
boiler key
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
13
Procedure
Control Panel
Over Heat Stat
Automatic Air Vent
Heating Elements
Copper Heat Exchanger
Printed Circuit Board
Voltage Free Control Connections
Circulation Pump
Flow & Return Sensors
Flow Switch
Pressure Guage
Expansion Vessel
Heating Flow
Heating Return
Pressure Relieve Valve
White Metal Enclosure